The present invention relates generally to vertical interconnect structures, and more particularly, to a three-wire-line vertical interconnect structure for use in interconnecting components disposed on a multilevel RF substrate.
Design engineers are just now beginning to take full advantage of the flexibility of multilevel substrates for RF circuitry. Good RF performance depends on the ability to transfer power between the various levels of the substrate without introducing excessive additional RF loss. The assignee of the present invention has developed an interconnect structure to provide for this type of interconnectivity that relates to planar radiator and RF interconnects. This is a coaxial feedline approach, but is relatively complicated, and is potentially difficult to fabricate. Furthermore, the coplanar waveguide feedline uses an edge-coupled device which may introduce greater RF loss than the structure of the present invention.
Active array radars for airborne applications typically require over 2000 transmit/receive modules per installation. Consequently, in order to provide for relatively affordable radars, each transmit/receive module should be made as inexpensively as possible, without sacrificing performance. The use of multilevel substrates provides a means for this goal to be reached, and also reduce the size and weight for airborne and space applications.
Therefore, it is an objective of the present invention to provide a vertical interconnect structure for use in interconnecting components disposed on a multilevel RF substrate that is adapted to transfer power between various levels of the substrate without introducing excessive additional loss.